Iwo Jima

Iwo Jima had no economic value, and it was chosen because of its position and its flat ground. It lay between the Marianas and Tokyo on the route of the B-29s, and the planners judged it the only island in the Volcano group that could support a large number of fighter aircraft. The Joint War Plans Committee listed four purposes in August 1944: fighter cover, denial of the island to Japan, air defence of the Marianas and the staging of heavy bombers. The American estimate in January 1945 put the garrison at 13,200 to 13,900 men and expected the Japanese to defend; the operation was approved on the expectation that the island could fall in about a week. The Marine Corps' count of the garrison on 19 February is 20,530 to 21,060.

Kuribayashi arrived in June 1944 with a plan that placed the defence inland. He did not contest the beaches, forbade large counter-attacks and arranged his men in mutually supporting positions that were to be held to the death. The tunnels and caves, in rock and concrete that the bombardment had barely touched, made the three days of preliminary naval gunfire less effective than the planners hoped. The Marines had asked for ten days, then nine, then four, and Turner and Spruance kept three for reasons of timing, ammunition and surprise. The official history calls the decision unfortunate, and Admiral Blandy wrote that substantial results came only after the ships had worked the objective for two days. How much longer fire could have achieved against concrete and rock is a question the evidence cannot settle.

The battle divided into three. The 28th Marines crossed the island's narrow waist on 19 February and took Suribachi by 23 February. The 3d, 4th and 5th Divisions then fought north in a line across the island, through Airfield No. 2, Hill 382, Turkey Knob, the Amphitheater and Hill 362, and the Marines reached the northeast coast on 9 and 10 March. The last phase was the reduction of the gorge at Kitano Point, which ended on 25 March, and the Japanese attack of 26 March. The two large counter-attacks the Japanese made, on 8 and 9 March and on 26 March, cost the attackers heavily, and the Marines took 25,851 casualties in the operation against the loss of almost all the garrison.

The weight of the island in the war is argued. The Army Air Forces wanted it for fighter escort and for emergency landings, and by the end of the war 2,251 B-29s with 24,761 crewmen had landed there, a figure that is sometimes given as about 2,400. Critics, among them the Marine officer and historian Robert Burrell, argue that few of those landings were genuine emergencies, that the escort role was small once the bombers turned to night raids, and that the Japanese radar warning continued from other islands. Supporters point to the crews who came down on the island. The retired Admiral William Pratt called Iwo useless as a staging base in April 1945, and the question of how many aircraft needed the island to avoid loss remains open.

The landing beaches lay on the island’s southeast side, below terraces of loose volcanic ash. Marine amphibious tractors could cross the surf, but their supporting fire was obstructed by a steep bank just inland. Men struggled for footing, vehicles sank or blocked the exits, and the accumulation of troops and stores provided targets for guns overlooking the beaches. Japanese fire grew heavier after the first waves had moved ashore. Reaching the beach and moving supplies beyond it became two different problems.

Kuribayashi had used the months before the assault to move the main defence away from the surf. Japanese troops enlarged natural caves, excavated new chambers, reinforced firing positions with concrete and gave many shelters more than one exit. The planned network of connecting passages was never finished, but its surviving sections allowed units to shelter from bombardment and reoccupy firing positions. At Suribachi alone the defenders occupied a sector with more than a thousand caves; the mountain could be isolated on 19 February without being cleared until four days later.

Northern Iwo presented another problem. Airfield No. 2 and the Motoyama plateau led into ground broken by ravines, steep slopes and mutually supporting positions. Hill 382, Turkey Knob and the Amphitheater covered one another, so attacking one strongpoint often exposed the Marines to fire from another. The defenders exploited a landscape in which a bunker could be bypassed without its occupants losing the ability to fire on the next movement. By March the battle depended on finding, isolating and destroying positions at very short range.

The dispute over preparatory bombardment ran through the American chain of command. Major General Harry Schmidt, whose V Amphibious Corps would make the landing, sought ten days of naval gunfire. Marine commanders subsequently argued for nine and then four days. Holland Smith supported the demands; Richmond Turner and Raymond Spruance retained the three-day schedule. Their reasoning included the availability of ammunition and ships, the timing of carrier strikes against Japan, and the risk that a longer preparation would give away the intended landing date.

The Japanese command followed a different calculation. Kuribayashi forbade costly attacks designed to throw the Americans back into the sea, directing his troops to hold prepared positions and exhaust the landing force. The order did not ensure uniform practice: army and naval sectors retained different chains of authority, and local commanders mounted counter-attacks, including the costly night attack of 8–9 March. American commanders also adapted. On 7 March Graves Erskine chose a surprise attack on Hill 362C without preliminary artillery, gaining ground that repeated daylight assaults had failed to secure.

Farther north, regular tank guns and naval fire could suppress an opening without destroying the tunnels behind it. Marine infantry worked with demolitions, flamethrowers and armoured vehicles to isolate entrances and close firing ports. Flame-equipped Shermans were especially valuable against caves and bunkers, though mines, anti-tank guns and broken ground made each approach hazardous. The defenders also used armour differently from an open-field battle: tanks from Nishi Takeichi’s 26th Tank Regiment were dug into fixed positions, trading mobility for concealment and protection.

The captured airfields began serving American forces before the island was secured. A damaged B-29 landed on Airfield No. 1 on 4 March, while combat continued to the north; more bombers followed before the end of the month. American fighters also began operating from the island, and P-51 escorts flew missions to Japan from April. The installations became operational in stages, so the military value of the airfields must be measured separately from the progress of the ground assault.

The Marine Corps official history records 25,851 Marine casualties by 26 March, with a further 2,798 Navy casualties among personnel supporting the operation. The campaign cost 6,821 American lives in that account. The Japanese garrison had been estimated at 20,530 to 21,060 men. Only a small number were prisoners when the Marines ended the capture phase; other survivors remained concealed and were taken later. The number of Japanese killed is reconstructed from incomplete records rather than a complete roll of confirmed battlefield deaths.

The island’s strategic result is more difficult to quantify. The official history lists 2,251 B-29 landings carrying 24,761 airmen by the end of the war, a substantial record of use. That total includes aircraft stopping for reasons other than imminent loss, however, and the number of lives saved cannot be obtained simply by treating every landing as an emergency. Fighter escort operations began only in April, while bombing tactics and targets were changing. The debate over Iwo Jima weighs genuine rescue and basing benefits against the high cost of taking it and against the alternatives available to American air commanders.

Whitman S. Bartley’s official Marine Corps history, Iwo Jima: Amphibious Epic, supplies the principal chronology of the landings, the fight for Suribachi, the northern strongpoints and the final Japanese positions. Its appendices distinguish dates, unit actions, casualty categories and estimated Japanese strength. The history also records the disagreements over naval preparation and the changing American estimates of the garrison, allowing contemporary planning assumptions to be distinguished from what the landing force later encountered.

The Japanese defensive system is reconstructed from captured information, surviving prisoners’ accounts and American battlefield observations, all of which have limits. Reports of final messages from Kuribayashi’s command need particular care because communications deteriorated and few senior defenders survived. Photographs provide firmer evidence for some specific moments—the landing, first flag raising, naval attacks and the first B-29 arrival—but a picture captioned simply “Iwo Jima, 1945” cannot be assigned to a precise day without an archival identification. Later assessments of the island’s value likewise depend on how an emergency landing, refuelling stop or fighter-escort mission is counted.